The goal of this proposal is to develop a rapid, specific, sensitive, and homogeneous detection system based on DNA amplification for the diagnosis of Chlamydia trachomatis infections in symptomatic as well as asymptomatic individuals. Chlamydia trachomatis is a major human pathogen responsible for a wide range of infections including lymphogranuloma venereum, trachoma, inclusion conjunctivitis and genital tract infections. The rapid identification of chlamydial infections is, therefore, essential for the proper treatment of infected patients and for the prevention of transmission to susceptible individuals. Presently used tests for C. trachomatis are either too slow, not sufficiently sensitive, very laborious, or susceptible to cross contamination. A homogeneous system based on DNA amplification and concomitant detection (SEConD amplification system) has been developed in Biotronics Corps. In phase I we propose to develop the amplification and detection primers for the SEConD amplification using the cloned C. trachomatis plasmid and genomic DNA sequences as targets. In phase H we win adapt this assay for direct detection of C. trachomatis in various clinical samples. Finally, we will perform a study to compare our assay with current protocols for C. trachomatis detection, i.e., cell culture method and direct fluorescent antibody techniques, and implement the methodology as a standard clinical assay.